This invention is directed to an adjustment mechanism for the alignment of a pivot bushing, trailing beam and axle of a vehicle. Vehicle trailers equipped with air ride suspensions may have an axle mounted on a pair of trailing beams with one trailing beam located on each side of the vehicle frame. The forward end of each trailing beam is pivotally connected to a bushing mounted in a housing which housing depends from a longitudinal extending beam on one side of the trailer frame. The bushing functions as a torsion spring to resist rotation of the trailing beam and to return the trailing beam to its initial position after rotation. Rotation of the trailing beam occurs as the axle moves up and down during travel of the vehicle.
In order to align and position the vehicle axle relative to the vehicle frame, it is necessary to move the pivot bushings on each side of the vehicle in forward and rearwardly directions. Each bushing is equipped with a shaft having non-continuous threads which provide right hand threads at each end of the shaft with each threaded end adapted to receive a locking nut. Elongated slots are formed in the side walls of the pivot bushing housing to receive the ends of the pivot bushing shaft and allow forward and rearwardly adjustment of the pivot bushing shaft upon loosening of the locking nuts. This has been the conventional method of adjusting the pivot bushings, trailing beam and vehicle axle of a vehicle.
The adjustment mechanism of this invention permits more accurate adjustments of a pivot bushing and also permits the adjustment to be made more quickly.
An object of this invention is an adjustment mechanism for a pivot bushing which allows precision adjustment movements of the pivot bushing and its shaft in forward and rearwardly directions through the use of a screw thread adjustment device.
Another object of this invention is an adjustment mechanism for a pivot bushing which positively holds the pivot bushing in its adjusted position until the holding nuts are tightened.
Yet another object of this invention is an adjustment mechanism for a pivot bushing which can be located on a bushing housing either in a location where it is less susceptible to tampering or in a location where it is more readily accessible to a mechanic.
Other objects of this invention will be found in the following specification, claims and drawings.